/**
 * Copyright (c) 2011-2014, OpenIoT
 *
 * This file is part of OpenIoT.
 *
 * OpenIoT is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation, version 3 of the License.
 *
 * OpenIoT is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with OpenIoT. If not, see <http://www.gnu.org/licenses/>.
 *
 * Contact: OpenIoT mailto: info@openiot.eu
 */
package org.openiot.cupus.artefact;

import java.io.Serializable;

import org.openiot.cupus.common.UniqueObject;

/**
 * Abstract Subscription class
 *
 */
public abstract class Subscription extends UniqueObject implements Serializable {

    private static final long serialVersionUID = 1L;

    protected long validity;
    protected long startTime;

    /**
     * Should not be used, created only for WS methods
     */
    public Subscription() {
        super();
    }

    public Subscription(long validity, long startTime) {
        super();
        this.validity = validity;
        this.startTime = startTime;
    }

    public long getValidity() {
        return validity;
    }

    public long getStartTime() {
        return startTime;
    }

    /**
     * Checks if validity is bigger than current time in millis or if it is -1.
     * If either of those is true then true is returned, else the publication is
     * invalid.
     */
    public boolean isValid() {
        return (validity >= java.lang.System.currentTimeMillis())
                || (validity == -1);
    }

    /**
     * Method returns TRUE if this subscription event matches publication pub.
     *
     * @param pub Publication to compare to.
     */
    public abstract boolean coversPublication(Publication pub);

    /**
     * Returns whether this subscription covers specified subscripion sub.<br>
     * Subscription A covers subscription B if A.equals(B) or (Type of A covers
     * Type of B and properties of A cover properties of B). Properties of A
     * cover croperties of B only if B contains all properties of A.
     *
     * @param sub Subccription to compare to.
     *
     * @return True if this sub covers specified sub, else false.
     */
    public abstract boolean coversSubscription(Subscription sub);

    public abstract String toString();
}
